In pressurized skin cleansing compositions, an aqueous liquid concentrate, generally an aqueous soap solution, is contained in a dispenser equipped with a dispensing head and valve, and pressurized with a normally gaseous propellant, e.g., a low molecular weight hydrocarbon or hydrocarbon mixture or a halohydrocarbon or halohydrocarbon mixture. Upon discharge of the emulsion through the dispensing head, the volatilization of the dispersed liquid droplets of propellant causes the dispensed concentrate to foam. Depending upon the precise formulation of the concentrate, the dispensed product may range from a dense creamy foam to a light foam.
The term "emulsion" will be used throughout this specification and claims to refer to the whole liquid contents of the dispenser, i.e., the emulsion concentrate plus water-soluble propellant, and the term "concentrate" will be used to refer to the liquid contents of the dispenser, other than the propellant, "liquid" in this context embracing solutions, emulsions and suspensions. In other words, the concentrate itself may be an emulsion or suspension and not necessarily a solution of the skin cleansing and conditioning ingredients in a suitable liquid medium, which, in the case of the present invention, will be water. The term "mousse", as used herein, refers to the dispensed product unless otherwise specified.
The cleansing of skin with surface-active cleansing preparations has become a focus of great interest. Many people wash and scrub their skin with various surface-active preparations several times a day. Ideal skin cleansers should cleanse the skin gently, causing little or no irritation, and without defatting and overdrying the skin or leaving it taut after frequent routine use. Most lathering soaps, liquids and bars included, fail in this respect.
Moisturizers such as glycerin provide skin conditioning benefits, and it is known to add moisturizers to skin cleansing products such as toilet bars and liquid and aerosol skin cleansers.
Emollients such as fatty glycerides, mineral oils and fatty alcohols provide smoothness and a protective coating to the skin. The use of these materials in skin cleansing products such as toilet bars, liquid and aerosol skin cleansing products is also known.
Skin cleansing products which produce voluminous lather generally require rinsing from the skin after application thereby resulting in a substantial loss of any moisturizers and/or emollients which may have been formulated into the product for conditioning of the skin.
Skin cleansing products, and in particular aerosol products containing moisturizers and emollients, can be formulated with low lathering, nonionic surfactants so as to reduce the need for rinsing. Such compositions, however, will not necessarily produce a mousse which has a pleasing creamy texture. Such texture is highly desirable for aesthetic reasons in a skin cleansing product.